1. Field of the Invention
The present invention relates to a cushioning support device that provides pressure redistribution, and a method for making the same. More particularly, it relates to a cushioning support device used in providing pressure support for a human body as well as a method for making the device.
2. Description of the Prior Art
Currently, a variety of commercially available seat cushions and back cushions are well known for their design to include a foam piece and a fabric piece combined together through an external force pressing process under high temperature conditions. There are two notable problems with the product made from this manufacturing method. On the one hand, when the foam piece tends to be thick, the product's buffering functionality is limited, and thereby resulting in sore experience. On the other hand, when the foam piece tends to be soft, the well-perceived elastic buffering functionality is compromised by making the user's body more susceptible to be caught up in the foam, thereby raising inconvenience for the user.
In view of these, prior technology has attempted to use needle sewing as a means to combine cushioning materials and fabric layers in order to enhance the buffering functionality of cushioning support product. Although such method of combination is capable of reducing degrees of collision and enhance ways to prevent such collision, there raises problems wherein the friction between user's skin and the woven works, resulting in skin ache or swollen skin and not to excluding skin wound or inflammation. Furthermore, the apparent woven works on the fabric surface is prone to wane down consumer's purchasing desire in terms of product appearance and functionality.
In addition to the aforementioned drawbacks, cushioning support device made from needle sewing has been observed to have the problems of easier release or break-off of the woven works, thereby leading to displacement of the cushioning material, and therefore causing inconvenience to the consumers. Indeed, the displacement of the cushioning material can significantly lower the cushioning material's desired benefits to the user's body parts.
Furthermore, different kinds of pressure-redistributing pads used for redistributing weight or pressure over a specific surface are everywhere in our daily lives. Examples are bubble sheets used for packaging fragile articles, rubber pads for use in providing structural support to items and reducing vibration, and soft pads for use in giving structural support for human bodies, such as mattresses, seat cushions, backrest cushions, and pillows. Of particular note among them is the soft pad for supporting for human bodies because it should not only provide soft comfort for its users, it must also have breathable, weight-redistributing, and human-body-supporting capabilities.
Currently known soft pads are designed to be made of different materials and by different structural configurations for the purpose of giving supportive, pressure-distributive, and soft effects. The materials commonly used in these include foam bodies, plastically deformable foam (polyurethane material), natural cotton, emulsions, and gels, where each material has their distinct properties and applicable conditions. Gels, for an example, are a plastic colloidal material known for their phenomenal pressure transferring capability and impact absorbing capability. The strong trend in increased number of pressure-redistributing pads using these gels is because of this reason.
Cushion matrix as discussed in U.S. Pat. No. 6,677,026 discloses a shock damping cushion that has a base sheet and a cover sheet welded together by use of heat or supersonics. In this invention the weld lines separate the damping region into a number of chambers presented in a rectangular arrangement, and gels or gel-like buffer materials fill the chambers therein, for which it is intended that the gels can work as a solution for resolving the conventional problem in which gas-filled (e.g. air) bubble sheets are not appropriate for application in bearing heavy weight or pressure-changing environment (e.g. air transport).
When the shock damping cushion of the '026 patent is used in providing structural support for articles, only the gels are used in bearing and redistributing the weight of the article. Each of the chambers filled with gels is an dependent space, and the gels therein are designed to fill the entire room in the chamber. When the gels are subject to weight compression and prone to change their shape, such can apply considerable pressure against the chamber, therefore the base sheet and the cover sheet in each chamber are required to have excellent resilience and strength, so as to avoid fracture. From another perspective, when the gels in the chambers are compressed to a level where no more shape changing is permissible, their buffer capability would decrease and would become more rigid as compared to when they are not compressed, this is an adverse effect that could result if the gel's permissible room for shape change is limited. In another perspective, in order to prevent the gels from leaking out of the base sheet and cover sheet due to compression, the breathability of the base sheet and the cover sheet should be of a less superior quality. This condition is at the same time indicating for the shock damping cushion to be required for disposition of a number of holes between every two neighboring chambers.
Although the shock damping cushion as discussed in the '026 patent can serve as a means for resolving the issues with conventional bubble sheets, the structure design of this shock damping cushion is fundamentally not appropriate for operating as a soft cushion for supporting a human body. The reason for this is because the level of comfort and breathability it can offer are not ideal to pass, and the resulting coordination between the human body and the shock damping cushion can easily create a discomforting sense.